As it prepares to endorse its first mayoral candidate in more than 20 years, the Boston Teachers Union will release a poll Wednesday that shows voters favoring candidates with similar beliefs in public education as the union.

That poll found that 73 percent of respondents said they favored a mayoral candidate who would work with the teachers union, rather than one who would “stand up to the teachers union because they are an obstacle to improving schools.”

Boston union president Richard Stutman said the poll would help teachers assess which of 12 candidates to support, which would include a get-out-the-vote effort. The union has more than 5,000 members living in the city, but so far has not decided when to issue its endorsement.

Stutman said the union would be less likely to support a candidate who is being backed by out-of-state organizations.

‘I think most citizens resent an outside and outsized financial backer coming in and telling them what to do.’

“It’s fair to say that some candidates are being unduly influenced by outside corporate funding,” said Stutman. “I think most citizens resent an outside and outsized financial backer coming in and telling them what to do.”

On Tuesday John Connolly
was endorsed by Stand for Children, a national education policy group that is often at odds with teachers unions for its support of charter schools and more rigorous evaluations of teachers.

Stand for Children is planning to spend more than a half-million dollars on advertising on Connolly’s behalf. He was also endorsed by Democrats for Education Reform, which also supports charter schools and has put roughly $26,000 behind Connolly.

Those contributions prompted the AFT to release the poll results, said federation president Randi Weingarten; previously, the federation planned to keep the results private, she said.

“Once we saw the money dump, we thought it was important to disclose what parents and the public actually think in Boston,” Weingarten said.

In a statement, Connolly said he would work diligently to bolster the quality of the city’s school system.

“As a former teacher and a [Boston public schools] parent, I believe that every child and every school should have the opportunity to succeed, and as mayor I will work to empower teachers, principals, and parents to build better schools,” Connolly said.

Paul Grogan, president of the Boston Foundation, which supports additional charter schools, said he doubted support for more charter schools is low. He noted that Boston’s 25 charter schools collectively have roughly 16,000 students on waiting lists.

“The poll that matters to me is demand,” Grogan said. “There is enormous pent-up demand in Boston for charter schools.”

Education has increasingly become the
dominant issue in the mayor’s race, with many candidates trying to position themselves as the “education mayor.”

The union poll did find dissatisfaction with the city’s school system. Sixty-six percent of respondents rated the system’s overall quality as fair, not so good, or poor. Another 27 percent rated the system as good or excellent.

The poll was conducted between Aug. 9 and 13 and involved 626 registered voters who were contacted by phone. It had a margin of error of 4.5 percent. Polling was done by Hart Research Associates.

Even though the union is critical of charter schools, a candidate’s support of a charter school would not necessarily be a deal breaker, Stutman said.

“It is possible to see a limited place for charter schools” in the city, he said.

So far, six candidates support additional charter schools to varying degrees: Connolly, former School Committee member John Barros, Suffolk District Attorney Daniel F. Conley, state Representative Martin Walsh, Bill Walczak, and former state representative Charlotte Golar Richie.

Four candidates oppose charter school expansion: Councilor at Large Felix Arroyo, radio station cofounder Charles Clemons Jr., Councilor Michael Ross, and Councilor Robert Consalvo.

Consalvo also has been pushing other candidates to decline contributions from outside special interest groups.

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